'City of Fresno'

[jemhouston]

It would be a shame if something fatal happened to 'Mater' Harris.

[Nik_SpeakerToCats]

Don't worry, I have plans for her...

[jemhouston]

Don't worry, I have plans for her...

My plan of tossing her out of the airlock would be more merciful.

[Nik_SpeakerToCats]

City of Fresno #49

After those intensive weeks working on the 'Front End' and 'Main Plant', then aboard 'Cwm Fahr', it was almost a holiday to load my booked laundrette machine, sprawl in a chair and half-listen to the other clients' cheerful chatter. And, yes, it was cheerful: The first 'Ponics lines 'planted', the first iceteroid gleanings 'fetched' had done wonders for morale. Okay, such were still 'Jam Tomorrow', but they were tangible. Now 'In the Pipeline', they were much, much better than airy Gantt Charts, plans and promises which 'Dire Lord Murphy' might easily up-end.

To my surprise, one of the clients, hunting around on the left view-screen's menu, found a sorta-documentary of my iceteroid gleaning. Split-screen, with my 'Big Mac' view synchronised to the 'Cwm Fahr' scans, it was a video-only version of what I'd used, 'frame by frame' to document my work. Lacking the complex 'overlays' and 'side-bars' of our many instruments, it was still remarkably dramatic. 'Whoosh !' In went a marker / anchor. 'Phwoom !!' The blaster's beam briskly excavated 'Trench One'...

That spectacular out-gassing was mostly harmless. But, such volatiles, freely fountaining into vacuum, carried sundry solids along. Those visible ice crystals and dust, harmless to a hard-suit, masked supersonic grit and, yes, pebbles. Both 'Big Mac' and 'Cwm Fahr' had glimpsed some of the latter using 'vog piercing' Terahertz. Call them 'Murphy Bombs', 'Out Flyers', 'Muskicetry' or worse, much worse. They'd shred a soft-suit, blind a hard-suit's sensors, damage tools and accessories, even strip antennae, attitude thrusters and such from unwary craft...

I was still shuddering at grim memories of others' oft-fatal 'Rock Hopper' mishaps, when one of the laundry machines began a brisk spin-cycle. Some-where in my subconscious, my modest 'Anti-Terrorist Training', euphemism for 'taking down' fanatics and Anwyc assassins, spiked. Spiked hard. Fresno's many, many docking-ports on each and every long, long 'leg' were almost indefensible given our meagre 'portable' armoury and total lack of 'Regional Militia', never mind Aerospace Marines. Worse, those tasers, side-arms and Bi-Guns had limited ammunition stocks. Very limited. We were years, multiple years, away from manufacturing more.

But, watching that laundry's whirl, I'd half-glimpsed a scarily elegant fix. Yes, I'd need to do a lot of research. Yes, we'd surely blow through a dozen prototypes. Still, with another nagging worry potentially resolved, I could sit back and enjoy the iceteroid show, 'Ooh !' and 'Aaah !' along with the rest of that busy laundrette's captivated audience...

[jemhouston]

Great foreshadowing tease

[Nik_SpeakerToCats]

Who-ever figures the docking leg defence notion may PM me with tag to name-drop...

[Nik_SpeakerToCats]

City of Fresno #50

Back in our suite, I sorted the washing, arranged it to air. Then, before taking another swing at documenting 'Hard Suit' prep and service procedures in near-layfolk language, I spared half an hour to pursue my notion. To my surprise, the scraps I'd remembered soon led me to useful sources. Jigsaw assembled, I sent a terse account plus my links to Lt. Richards. After a deep breath, I switched tasks to again revising the training materials' draft.

Anne-Marie had mentioned she'd be in the other Drum for most of today, so I ate my forgettable lunch alone. Back in the suite, with both view-screens crowded by the current section's text versions plus the graphics and lists they referenced, I slowly made progress. Urgently studying the 'Partridge' 'Ponics folder and drafting that skills survey under my partner's oft-sarky tutelage had rapidly taught me a lot about pace and formatting for non-specialists. I'd have to let her look over this work, to be sure, to be sure, but I reckoned she'd be reasonably pleased. As it happened, I'd taught Anne-Marie enough about 'Big Mac' to start up the life-support systems 'in extremis'...

With an equally forgettable evening meal sat in my tum, I was 'combing out' another potentially ambiguous paragraph when the view-call chimed. Lt. Richards was on the line.

"Mr. Kinson, thank you for that idea. The initial response from Engineering is very favourable. It uses non-essential materials and resources, does not expend primers and such. As you said, some prototyping will be required...

"May I ask what prompted this ?"

"Doing laundry this morning." I grinned as his eyebrows rose. "Every-one was watching the video footage of my ice-slicing. Happens that version lacked the overlays and side-bars which warned us of scary 'Out-Flyers' hiding in the vog. Yes, my suit's Tera-Hertz Doppler data had wide error-bars due Sin(i) of near-transverse motion, but 'Cwm Fahr' logged sundry 'Supersonics'...

"Then a spin-cycle came on. It triggered a tangential associative cascade..."

"Which took you from 'Hither' to 'Yon'." Lt. Richards took a slow breath, a second. "Tangential, indeed. Thank you."

"No problem..." I shrugged. "Some-one would have thought of it soon enough."

"That's... Debatable," he allowed. "In other business, I'm sorry, your excellent proposal to use 'heavier' tholin content to fertilise microbial broth to produce fibre precursors must be deferred. Producing food must take priority.

"I think it is safe to say Fresno's 'Honeymoon Period' is over: The aft Diner in the other Drum has been 'Hacked'. Some-one found a way to dispense extra meals. So, for some weeks, hundreds of additional portions were consumed each day. How many is still unclear, there's an urgent 'stock' audit in progress, but this has put a big, big hole in their rationing logistics."

I blinked, ran the math. "Nasty. Margins were already tight. Uncomfortably tight. Will this drum need to 'lend' some stock ?"

"Probably..." He sighed. "It was your clever partner, working long, long hours, snatching meals where and when she could, who spotted the problem. She's earned another 'Captain's Commendation'...

"I must ask you to hold this in confidence, as we're trying to contain and mitigate the consequences."

"The perps ?"

"We think the hack was accidental rather than malicious. Sadly, rather than report the matter, the procedure was spread by 'Word of Mouth'..."

"It's been blocked ?"

"Yes, just needed changing a default 'admin' password."

"Huh." I shook my head. "Well, they'll all take an immediate 25% hit to their diet. That will bite, and early perps, hardest..."

"Hopefully, punishment enough for now."

"Plus a warning flag against their confidential medical records ?"

"That, too, Mr. Kinson. That, too..."

[jemhouston]

You know some temperature cycling in the area might be in order.

[Nik_SpeakerToCats]

The culprits number but several hundred of the two thousand-ish in drum: If you cannot identify them unambiguously, how can you punish justly ?

No, losing their extra meals will bite perps hard, and the earliest hardest...

[Nik_SpeakerToCats]

City of Fresno #51

Given news of the Diner hack, I found it hard to concentrate on editing the training course. Still, I stuck at that document, glumly ground through a few more sub-sections. It was late, really late when Anne-Marie returned. She was pale, stressed scary-tight.

"I heard," I opened. "Lt. Richards called some hours ago."

"Hours ?" She managed. Her strong shoulders slumped. "Jake, it's worse. Much worse. I can't see how or why it wasn't spotted sooner, but a lot more people than we first thought have been 'freeloading'. Mostly the other Drum's Aft Diner. Ramping up in their Forward Diner, begun over here."

"The password change ?"

"Yes, yes, that's put an end to it..." She shook her head. "But our quick audit found Fresno's down by at least a week's rations. And unevenly, so possibly more. We'll have to transfer a dozen ingredient IBCs around to level-up. A Bakers' dozen. Possibly more. And limit menu options to cover prior excess usage."

"The MREs ?"

"Really, really last resort. They're our 'Hole Card' against Murphy Bombs."

"Shoulder massage ?"

"Please..." She sprawled prone onto the lower bunk we used as a couch, groaned as I sank strong fingers into her tense muscles. "Oh, Jake ! Every-thing seemed to be going so well !!"

"Looks like we won't be brewing these tholins into fibre-stock."

"Yeah..." She flinched as I hit a 'knot'. "Instead, we'll have to bake out what volatiles we can, then hydrolyse and hydrogenate 'residuals' to really basic compounds as 'Fixed Nitrogen' fertiliser."

"Figures..." I hesitated, asked, "Do you know if the plan to move Fresno nearer the iceteroid came before or after discovering the hack ?"

"Huh ?" Anne-Marie took a moment to back-track my logic. "Jake, you have a delightfully devious mind: No, the move was planned as soon as 'Cwm Fahr' sent those preliminary reports on percentages and dust density."

"But they waited for the full data, to be sure, to be sure ?"

"Sounds right-- Ugh !" She flinched as I hit another knot. "With hind-sight, we could have spotted something was wrong in that drum weeks ago."

"How so ?"

"Well, remember you mentioned how we'd recover water from the HVAC as rationed people slimmed down ?"

"Uh, yes ?"

"All four drum halves were tracking similarly until some weeks ago, but then the slightly lower recovery rate from that half began to fall behind. Further and further, faster and faster. Engineers probing and checking the HVAC could not find anything wrong..."

"Ha !!" My clench made her squeak. "Those perps face an immediate 25% cut in their rations, they'll soon lose weight so fast..."

"Nearer 30%," Anne-Marie warned. "These new, improved menu options will mask taking another belt-notch."

"Huh..." I shifted my aim, drew another squeak. "Lt. Richards said this marks the end of Fresno's honeymoon period."

"Well, it's true. Happens I said that to him."

"Shows he listens to good sense."

"Uh-Huh... Left hand down a little ? You got it..." She shook her head. "I've not seen Lt. Richards angry before. Wasn't pretty. I thought he was going to break out the small-arms and storm into that Drum with a posse."

"Tempting," I admitted.

"Two of the 'Level Two' trainees talked him down. Jake, remember that fun 'Folk' concert on Chaparral ?"

"Uh..." It already seemed a lifetime ago. "Uh ? Older couple ? 'The Gillespies' ? Mandolin and Mandola ?"

"That's them." Anne-Marie nodded. "Even I thought Jay and Joe were just 'Travelling Troubadours', collecting folk-songs, granny-tales and rhymes. Who'd bravely stayed for the 'Last Train' to give concerts, keep up morale."

"It did. Unlike you, I'm not particularly musical, but they took my mind off that frantic scramble for a couple of very welcome hours."

"Seems they're honest -to- goodness Ethnographers by trade, sent by BETA to document Chaparral society and mind-sets before the big lock-down-- Hey, don't stop !"

"Sorry..." I gathered my wits, renewed my massage. "Ethnographers ? So, 'People-Savvy' ?"

"Very. They told Lt. Richards that serial perps suddenly losing their 'bonus' meals would be punishment enough for now, but to flag their records."

"That makes sense..." I worked down her spine, mused, "The Ship Council ? Will they get one seat ? Or two ?"

"Just one," Anne-Marie said. "Plus a deputy with 'Observer Status' and proxy-vote. Same as us."

"Huh ?"

"Same as us." She rolled her shoulders. "Ooh, thank you, Jake ! That's so much better ! Let's grab a shower..."

After a rather sombre shower, we went to bed but, like that first night, cried ourselves to sleep on each-other's shoulder.

[Nik_SpeakerToCats]

City of Fresno #52

Morning brought bleary eyes, inadequate breakfasts, a queue of issues to tackle. Anne-Marie stomped off towards the 'Ponics. I took another swing through a reluctant paragraph, managed to make it read better. Then I got a text-mail from Ms. Betrys, with a link to CCTV of this first gleaning's bake-out.

Fresno's engineers had connected to several 'man-hole' ports in the 'Collection' tank, begun beaming infra-red at the heaped contents. Fresno's tiny 'ullage' thrust plus 15-minute 'Barbecue Roll' meant our chunks and lumps were mostly at the stern, untidily piled to one side. Out-gassing soon brought that alive. Side-bars showed furiously fizzed volatiles being sucked away towards the 'Main Plant'. As the tank interior warmed up by slow degrees, it reached an important phase-change temperature. That frozen gas sublimed freely, the pile went wild. Though scary, the lumps were too big, too slow to do damage. And, such collisions progressively fractured 'bergy-bits' to smaller and yet smaller chunks, so their out-gassing rapidly accelerated.

With that first big threshold mostly complete, the temperature again began to rise. Another abrupt out-gassing developed. And then a third, a fourth. Each time, the out-flow content shifted significantly. Then came the 'Big One'. We'd reached the 'Snow Line'. Water-ice began to sublime in quantity. The 'Main Plant' slurped vapour, spun-out solids, filtered fines. The water, re-distilled under reduced pressure, fed a big holding tank. Hopefully, by the end of the day, several one-tonne IBC tanks could be filled and ferried to each waiting 'Ponics line.

Though such 'Sneaker Net' seemed inefficient, for these quantities it was much, much faster, simpler, easier than cross-connecting the 'Main Plant' to Fresno's complex distribution systems, purging and 'pigging' lines, delivering thus. Things would be so different when Rock Tugs began catching a dozen kilo-tonnes of iceteroid a day...

As the water vapour flow-rate subsided, an adapted 'Mantis Grapple' reached in and deployed a high-pressure water jet. This sliced, diced, demolished remaining lumps and chunks. Now the 'Main Plant' centrifugal solids separator came into its own, sent wet minerals and tholins swirling into a 'silo'. This fed a heated spiral which, with added hydrogen, boiled, pressure-cooked, hydrolysed and hydrogenated the mix. Before evolved gasses could re-dissolve, they were spun out and cross-fed to the gas handler. The hot water was vacuum-evaporated and recycled, leaving only minerals behind.

Studying this broiled residue, comparing it to pristine samples was on my 'To Do' list. Meanwhile, I'd an hour of editing and a few notions to research before lunch...

The mood in our Diner was grim. Word of the 'Hack' had now circulated widely, the meagre consequences clear to see on every plate. Opinions varied from 'Solitary Confinement' through 'Percussive Maintenance' to 'Long Walks out of Short Air-Locks'.

But why no formal sanctions ??

I mentioned that the sudden loss of their 'bonus' meals would so bite the perps, and the earliest, the worst. It drew chuckles, even a few laughs, plus a wry comment that we knew at least one group had not indulged. Eyes duly turned to the Diner doorway, through which 'Mater' Harris' ever-shrill complaints would soon be heard...

[jemhouston]

'Mater' Harris' is now a source of humor or derision?

[Nik_SpeakerToCats]

She is an 'Institution'...

With grudging kudos for not 'free-loading' on the Diner system, tempered by head-shakes for still tithing her hapless minions' meals...

[Nik_SpeakerToCats]

City of Fresno #53

Afternoon brought yet-more reluctant paragraphs, which I slowly wrangled into submission. My evening meal was only memorable for its scant portions. I worked late into the evening. Really late. As far as I knew, Anne-Marie had never bunked else-where. I was beginning to wonder if, exhausted, this was a first, when I heard her weary footsteps outside.

"Hug ?" Anne-Marie pleaded, landing a chunky sample case. "Back-rub ?"

Our long, close clinch was followed by me methodically attacking her tensed muscles.

"That's so good, Jake," she reported after a while. "Engineers send their compliments and some annotated samples. They delivered tonne IBCs of water as soon as each filled. We managed to get four --Four !!-- new 'Ponics lines up and running."

"Four ?" I dug fingers into her knotted shoulders. "Wow ! A week sooner than I'd expected."

"Well, the 'Ponics trainees were very motivated." She sniffed. "A lot of 'Angry are Us !' Most knew people who ate at odd times, were not losing weight. None flagged them as 'Freeloaders'-- Hey, this is the 'Convention' ! We do not cheat !"

"Yeah..." I targeted Anne-Marie's shoulders. "But are we still the 'Convention' ?"

"Too right, Jake. Uh, down a bit on the left ? Oooh..." She shook her head sharply. "Looks like the Gillespies get material for a spicy educational report..."

"Very spicy..."

"You reckon they'll publish any-where but Fresno's library ?"

"I... I don't know." I took a moment to think. "Provided the 'Others' lose before there's too much damage, the Sylvans and their allies may want to push outwards. Not towards 'Other' space. A lot of real-estate along their 'border' was thermo-nuked, is 'Hot'. Not towards Earth: We've grabbed the good stuff, plus a bunch they wouldn't touch. Not towards Anwyc Space. Well, at least not yet. Humbling them is on BETA's 'To-Do' list after resolving the 'Others'. Beyond Autumn, the 'Others' razed at least one planet's indigenes. Blasted those back to the Stone Age, then off the map. Needs another century before archaeologists dare investigate beyond rad-hardened drones...

"No, given the remaining options, I reckon the Convention / Sylvan Alliance will explore this way." I shrugged. "Provided the 'Others' lose, a proposed 'Capital-Class' star-ship would be able to ferry 'Trojan-Class' tugs, 'Pleiades' mega-tugs and several complete 'Gas Stations'."

"Refuel in the time it takes to survey a system ?"

"Easily. But space is big, very big, and we're a long, long way from home." I took a breath. "Fresno should have had a bunch of message torps. Like those launched by Ember's watch-stations ? Half-kin to beacon-buoys. Okay, there's no way a torp could get back from here on its own. Even with big auxiliary tanks, they simply do not have the range, FTL speed or 'Smarts'. I cannot find any record of how many torps were on board at Chaparral. Only that Fresno now lacks its full complement--"

"Fresno left a 'Bread-crumb Trail' ?"

"It's just possible--"

"If launched near 'Convention Space' ?"

"If they survived the shock-wave." Unseen by Anne-Marie, my shrug was Gallic-eloquent, but my voice betrayed deep doubt. "If the first torps get home. If their data makes sense. If enough subsequent torps get found, extend the search-vector..."

"That's a lot of 'Ifs' and 'Buts', Jake," Anne Marie agreed. "I'm not surprised that possibility was not discussed ! Too much of a 'Hail Mary Pass' !"

"Agreed." I sighed. "And assumes the 'Others' lose without tearing everything down in flames."

"Huh ? A 'Sampson Option' ?" Anne-Marie shuddered. "You mean 'Vengeance Weapons' ?"

"Too right ! From what I've read, the Sylvans reported each 'Other' system is mined 'Up the Wazoo'. Improbable guard ship and missile platform counts. Kerb-stomp any attempt to send probes in-system." I hesitated, added, "I'm no 'Insider' but, reading between the lines, seems the 'Akkkan', one of the Sylvans' mostly-peaceable neighbours, replied to their first 'Other' attack with a desperate Kamikaze strike. Took out an entire 'Other' colony and its well-defended 'Fleet Supply Base'. Put the 'Others' on the defensive for almost a decade, just long enough for the Sylvans to organise an alliance and arm-up. Since then, it's been 'War to the Knife'."

"Ugh..." Anne-Marie sounded disgusted. "That's horrible !"

"Yes..." After a slow breath, I added, "I'm afraid so..."

"But, 'Vengeance Weapons ?"

"Each 'Other' ship's 'Achilles Heel' is their need for anti-matter fuel." I held her shoulders, managed to say, "If they only carry enough for bombs and a 'Death Ride'--"

"Planet killers !" Anne-Marie hissed, pleaded, "Jake, I've the shivers: I need a hot shower, a back-soap..."

"You're on..."

[jemhouston]

Grim thought

[kdahm]

"Each 'Other' ship's 'Achilles Heel' is their need for anti-matter fuel." I held her shoulders, managed to say, "If they only carry enough for bombs and a 'Death Ride'--"

"Planet killers !" Anne-Marie hissed, pleaded, "Jake, I've the shivers: I need a hot shower, a back-soap..."

This sounds odd to me. As soon as there is heavy industry, rock tugs, and moving multiple tons of asteroids around, planet killers are easy. Very much like chemical warfare agents when there are refineries spanning multiple square miles doing their thing (and exploding occasionally). If they haven't considered how to use what they already have as planet killers, I'd be surprised.

Also, tracking of meals served vs. population has very much been implemented.

[Nik_SpeakerToCats]

Space is BIG: Sure, you can tip iceteroids out of the Kuiper Belt and/or Oort cloud to 'Long Period Comet' dives, but they'll take a long time to reach inner-system. By when, the locals will have had ample time to track the incoming, rendezvous, divert, or simply shatter to below 'scary' threshold.

Unlike ST/SW where ships go to warp from LEO, mine must get a significant distance up system's g-well, where gravity gradient / slope of g-well is sufficiently low. It's harder for bigger ships, as equivalent of 'tidal forces' mean they must wait until further out. And, similarly inbound. Getting it wrong breaks your OverDrive. Getting it really wrong efficiently ( = mc²) converts your ship to a spectacular blue flash of Cherenkov radiation. Usually, too far out to damage in-system facilities beyond the mine or hapless missile platform / guard ship you've over-run...

No, to breach a 'well-defended' system, you gotta come in crazy-fast, preferably from an unexpected, perhaps sub-optimal direction. A 'classic' flank attack, in fact. Yes, such in-bound speed means you must lead with a dust / gravel kinetic screen, and replenish it. Speed shortens your final-targeting / weapon-release window, but does let you coast back up / out of star's g-well to the 'Overdrive Limit'.

This is the 'Reconnaissance in Force' / 'Hit & Run' tactic used by the Others' Taggli 'Battle-cruisers' at eg Trilorn.
When it works, it is excellent. When your opponents think 'outside the box', not necessarily so...

[kdahm]

Yes, from the way the tech was described, there are a lot of things that can be done. Pick up a 300m nickel-iron bolide, drop it off outside of detection range in one of the polar directions from the ecliptic, and use a drive to accelerate to 0.1c. Even a 100m rock would be enough. Either every world has to be a fortress with significant resources devoted to protecting it or even just finding such threats, or something gets through. And anything that can do substantial damage to a solid 100m or 300m solid bolide will do devastating damage to a planet's surface.

The engineers of the Convention probably have a list of such things. The smart ones consider other things to see if they should be added, or even published. Anti-matter and death rides are just one option. Although granted, Anne-Marie may not have been in the fortunate group having to think of the list.

[Nik_SpeakerToCats]

City of Fresno #54

The following morning, after our meagre breakfasts, Anne-Marie stomped off towards the 'Ponics. Over-night, a line's chemistry had drifted to the edge of its optimal range. Several cross-checked sensors concurred. At least it was not a new, 'iceteroid-watered' system. Such coincidence would have raised nape-hair. Whatever, a fix had eluded the weary staff. She and I agreed that, hopefully, cause and solution were so obvious they sat in plain sight, like misplaced tools or keys. If not, the fault-finding decision tree might need a tweak: Perhaps comb out and clarify an unfortunate ambiguity, perhaps add a new 'Check / Try This' trap...

I did several tedious hours of hard-suit procedure editing, took a short break, then turned to the sample case. As Ms. Betrys had initially reported, our iceteroid was, to a first approximation, 'Generic Halley'. Further analysis of sundry samples simply extended the data set, adding precision and lengthening the list of lesser components. Yes, we knew the un-sampled interior was some-what heterogeneous. Yes, we'd partially mapped the biggest anomalies with Radar and as 'MasCons'. Yes, for each such, there'd surely be several smaller, below our detection threshold. Then, beyond, we expected a 'Power Law' distribution of smaller and yet smaller, all the way to that near-fractal dust. I was glad the rock tugs and their ice-slicer turrets would be dealing with the less-predictable deeper material.

I studied the Engineers' latest reports on this first collection. It included welcome confirmation that our 'five hundred tonnes' estimate for water recovery had been exceeded by a dozen percent, plus what was now circulating 'In The Main Plant'. Fresno's Doc. Meredith had run analyses on the raw and in-process tholins, found no surprises. Safely cooked, the carbon, as dioxide, would soon be fed to our briskly photo-synthesising 'Ponics. The nitrogen was now available as fertiliser. Anne-Marie would be pleased. Though staggering planting and cropping was essential, she claimed some flexibility. Being able to significantly supplement a 'Ponic line's feed further extended options.

I turned to the mineralogy. There was a borderline-gleeful report by the Engineers detailing the multiple ways they'd tackled the near-fractal size-range of those extracted solids. Cold-discharge, Arc-discharge, RF discharge from a Tesla Coil, a re-purposed microwave oven, a spun 'Lava Lake'-- All had worked well, to their various teams' evident delight. One item was obvious: This first glean totally lacked the 'Chrondrule' inclusions common to many in-system objects, from asteroids down to bolides. Based on our limited sampling, this iceteroid was 'Achrondrite'. Those deeper 'anomalies' might well include such, but this initial glean was clearly from outer-system material. Equipped for 'rocky' moons, I lacked the instruments for better, but several suggestive trace-isotope ratios plus the absence of 'hot' Al_26 implied this iceteroid had been in the 'Deep and Dark' for about half a billion years, two entire galactic orbits. Though rather younger than Sol-System's equivalents, which 'clocked in' at four and a half billion, give or take, it was certainly not a recent arrival from any near-by star-forming region. That half-billion was ample time for even spicy, young, T-Tauri stars to settle down, collapse their primordial nebula to multiple proto-planetary cores and a few gas-giants.

Okay, those would then progressively interact via orbital resonances and epic collisions. Earth got our Moon thus. And, based on 'legacy' gaps in the asteroid belt, looks like Jupiter initially spiralled inwards through the still-busy solar nebula, swallowing or scattering stuff. Then a developing 'resonance' with Saturn gave pause, retreat. That was the Nice 'Grand Tack' claim. Though an extraordinary 'Pre-Burn' notion, we'd found nothing to falsify it, and much supporting evidence. Worst case, Jupiter could have continued inwards, engulfing Asteroid Belt, Mars and Earth/Moon or proto-Earth / Mars-sized Theia. Perhaps even de-stabilising the orbits of Venus and Mercury. Had matters been slightly different, Sol-system could have a 'warm' or 'hot' Jovian instead of three of our four rocky planets. And, perhaps, if that in-spiral halted in the 'hab-zone', said Jovian might have acquired a 'potentially terrestrial' mega-moon...

In fact, such a 'Jovian plus tidally-stirred mega-moon' pairing seemed much, much more probable than the serendipitous outcome of that proto-Earth / Theia collision. How did their 'Big Splat' toss enough mantle debris from both into a sufficiently stable orbit to bake out, then clump to our big Moon ? And, did massive fragments from Theia's impact seed our 'Plate Tectonics' ? Each was a 'WTF ??' to bemuse astronomers and geologists alike, never mind those enigmatic 'Priors'...

[jemhouston]

Planets unless named Krypton don't blow up by themselves.